* Split development and deployments requirements files out
* Add `Authentication Insight` to payment method nonce create
* Add ThreeDSecure test payment method nonces
* Add test `AuthenticationId`s
* Add `three_d_secure_authentication_id` to `three_d_secure_info`
* Add `three_d_secure_authentication_id` support for transaction sale
* Breaking Changes
* Require Python 3.5+
* Remove deprecated Transparent Redirect
* Remove deprecated iDeal payment method
* Apple Pay register_domains returns an ApplePayOptions object
* Remove `unrecognized` status from Transaction, Subscription, and CreditCardVerification
* Remove `GrantedPaymentInstrumentUpdate` kind from Webhook
* Remove Coinbase references
* Add GatewayTimeoutError, RequestTimeoutError exceptions
* Rename DownForMaintenanceError exception to ServiceUnavailableError
* Transaction `line_items` only returns the line items for a transaction response object. Use TransactionLineItem `find_all` to search all line items on a transaction, given a transaction_id
* Upgrade API version to retrieve declined refund transactions
* Remove all deprecated parameters, errors, and methods